Augustine of Hippo

He is God, so he also takes pity. He gets angry, and he takes pity. He gets angry and strikes; he takes pity and heals. He gets angry and does to death; he takes pity and brings to life. In one person he does this. It's not that he does some people to death and brings others to life, but in the same people he is both angry and gentle. He is angry with errors; he is gentle with bad habits put right. …

Sermon 24.7 ↗

Hilary of Poitiers

The true method of our enquiry demands that we should begin with him, through whom God first manifested Himself to the world, that is, with Moses, by whose mouth God the Only-begotten thus declared Himself; See, see that I am God, and there is no God beside Me. That godless heresy must not assign these words to God, the unbegotten Father, is clear by the sense of the passage and by the evidence of the Apostle who, as we have already stated, has taught us to understand this whole discourse as spoken by God the Only-begotten. …

On The Trinity 5:36 ↗

Bonaventure

It must be said that this truth, that God is one, is a truth not only believable, but also intelligible: since it is necessary and certain not only from the testimony of Scripture and the illumination of grace, which is found in faith; but it is also certain from itself and from the testimony of creatures. From itself, therefore: because the divine being, on account of its singular sublimity and sublime singularity, possesses unity in every way. …

Disputed Questions on the Mystery of the Trinity, Question 2 ↗